Justification:
This species is common within a relatively restricted range. There has been an estimated 29% decline in mangrove area within this species range since 1980. However, it is easily propogated, is a hardy species, and its range is increasing in Japan. This species is listed as Least Concern.

This species is found in southern Viet Nam, China, Taiwan, Japan, and only on Natuna Islands in Indonesia. Its range may also extend to the extreme north of Philippines, although this needs to be confirmed. This species distribution is increasing to the north in Japan (at least present now to 35 degrees N).

This species is found in the downstream estuarine zone in the lower intertidal region (Robertson and Alongi 1992). This species is easily propagated, and coppices. It is considered a hardy species, although is relatively slow-growing (5 years to grow 1.5 m). This species generally grows up to about 3 meters.

Although local estimates are uncertain due to differing legislative definitions of what is a 'mangrove' and to the imprecision in determining mangrove area, current consensus estimates of mangrove loss in the last quarter-century report an approximately 29% decline in mangrove areas across China, Japan countries within this species range since 1980 (FAO 2007).

All mangrove ecosystems occur within mean sea level and high tidal elevations, and have distinct species zonations that are controlled by the elevation of the substrate relative to mean sea level. This is because of associated variation in frequency of elevation, salinity and wave action (Duke et al. 1998). With rise in sea-level, the habitat requirements of each species will be disrupted, and species zones will suffer mortality at their present locations and re-establish at higher elevations in areas that were previously landward zones (Ellison 2005). If sea-level rise is a continued trend over this century, then there will be continued mortality and re-establishment of species zones. However, species that are easily dispersed and fast growing/fast producing will cope better than those which are slower growing and slower to reproduce.

In addition, mangrove area is declining globally due to a number of localized threats. The main threat is habitat destruction and removal of mangrove areas. Reasons for removal include cleared for shrimp farms, agriculture, fish ponds, rice production and salt pans, and for the development of urban and industrial areas, road construction, coconut plantations, ports, airports, and tourist resorts. Other threats include pollution from sewage effluents, solid wastes, siltation, oil, and agricultural and urban runoff. Climate change is also thought to be a threat, particularly at the edges of a species range. Natural threats include cyclones, hurricane and tsunamis.

This species range may include some marine and coastal protected areas. This is a protected species in Taiwan. In Japan, this species has been planted for at least the past 100 years. In Viet Nam, this species is planted as protection from coastal erosion and storms.

Continued monitoring and research is recommended, as well as the inclusion of mangrove areas in marine and coastal protected areas.